RESUMO
Seafood represents a significant part of the human staple diet. In the recent years, the identification of emerging lipophilic marine toxins has increased, leading to the potential for consumers to be intoxicated by these toxins. In the present work, we investigate the presence of lipophilic marine toxins (both regulated and emerging) in commercial seafood products from non-European locations, including mussels Mytilus chilensis from Chile, clams Tawerea gayi and Metetrix lyrate from the Southeast Pacific and Vietnam, and food supplements based on mussels formulations of Perna canaliculus from New Zealand. All these products were purchased from European Union markets and they were analyzed by UPLC-MS/MS. Results showed the presence of the emerging pinnatoxin-G in mussels Mytilus chilensis at levels up to 5.2 µg/kg and azaspiracid-2 and pectenotoxin-2 in clams Tawera gayi up to 4.33 µg/kg and 10.88 µg/kg, respectively. This study confirms the presence of pinnatoxins in Chile, one of the major mussel producers worldwide. Chromatograms showed the presence of 13-desmethyl spirolide C in dietary supplements in the range of 33.2-97.9 µg/kg after an extraction with water and methanol from 0.39 g of the green lipped mussels powder. As far as we know, this constitutes the first time that an emerging cyclic imine toxin in dietary supplements is reported. Identifying new matrix, locations, and understanding emerging toxin distribution area are important for preventing the risks of spreading and contamination linked to these compounds.
Assuntos
Ração Animal/análise , Suplementos Nutricionais/análise , Iminas/análise , Toxinas Marinhas/análise , Mytilus/química , Perna (Organismo)/química , Alimentos Marinhos/análise , Compostos de Espiro/análise , Ração Animal/toxicidade , Animais , Aquicultura , Suplementos Nutricionais/toxicidade , Contaminação de Alimentos , Iminas/toxicidade , Toxinas Marinhas/toxicidade , Medição de Risco , Compostos de Espiro/toxicidadeRESUMO
Phenylpyrazole insecticides are successful for crop protection and public hygiene by blocking gamma-aminobutyric acid (GABA)-gated chloride channels and glutamate-gated chloride (GluCl) channels. A series of novel phenylpyrazoles containing arylimine or 1-methoxyaryl groups were designed and synthesized. The addition reaction of methanol to the imines 1-11 was investigated and the cayno addition products 13-15 were obtained. The compounds 1-15 were confirmed by 1H NMR and elemental analysis. The results of bioassay indicated that some compounds exhibited comparable bioactivity to fipronil against a broad spectrum of insects such as bean aphid (Aphis craccivora), mosquito (Culex pipiens pallens), diamondback moth (Plutella xylostella) and Oriental armyworm (Mythimna separata). Especially, the foliar contact activity against bean aphid of compound 7 at 10⯵gâ¯mL-1 was 68%, the larvacidal activity against mosquito of compounds 5, 13 and 15 at 0.0025⯵gâ¯mL-1 was 100%, the larvacidal activity against diamondback moth of compounds 9 and 11 at 0.05⯵gâ¯mL-1 was 100%, the larvacidal activity against Oriental armyworm of compound 9 at 1⯵gâ¯mL-1 was 100%. The 3-cayno moiety on pyrazole ring was essential for the high insecticidal activities against bean aphid, diamondback moth and Oriental armyworm, while the 3-carbimidate moiety on pyrazole ring was crucial to the excellent high insecticidal activities against mosquito.
Assuntos
Iminas/toxicidade , Inseticidas/toxicidade , Pirazóis/toxicidade , Animais , Desenho de Fármacos , Iminas/síntese química , Insetos/efeitos dos fármacos , Inseticidas/síntese química , Larva/efeitos dos fármacos , Estrutura Molecular , Pirazóis/síntese química , Relação Estrutura-AtividadeRESUMO
Among toxin-producing dinoflagellates of the genus Alexandrium, Alexandrium ostenfeldii is the only species able to produce paralytic shellfish poisoning (PSP) toxins, spirolides (SPXs) and gymnodimines (GYMs). In this study we characterized and compared three A. ostenfeldii strains isolated from the Baltic, Mediterranean, and southern Chile Seas with respect to their toxin profiles, morphology, and phylogeny. Toxin analyses by HPLC-FD and LC-HRMS revealed differences in the toxin profiles of the three strains. The PSP toxin profiles of the southern Chile and Baltic strains were largely the same and included gonyautoxin (GTX)-3, GTX-2, and saxitoxin (STX), although the total PSP toxin content of the Chilean strain (105.83 ± 72.15 pg cell(-1)) was much higher than that of the Baltic strain (4.04 ± 1.93 pg cell(-1)). However, the Baltic strain was the only strain that expressed detectable amounts of analogues of GYM-A and GYM-B/-C (48.27 ± 26.12 pg GYM-A equivalents cell(-1)). The only toxin expressed by the Mediterranean strain was 13-desmethyl SPX-C (13dMeC; 2.85 ± 4.76 pg cell(-1)). Phylogenetic analysis based on the LSU rRNA showed that the studied strains belonged to distinct molecular clades. The toxin profiles determined in this study provide further evidence of the taxonomic complexity of this species.
Assuntos
Dinoflagellida/isolamento & purificação , Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Hidrocarbonetos Cíclicos/isolamento & purificação , Iminas/isolamento & purificação , Compostos de Espiro/isolamento & purificação , Chile , Cromatografia Líquida de Alta Pressão , Dinoflagellida/classificação , Compostos Heterocíclicos com 3 Anéis/toxicidade , Hidrocarbonetos Cíclicos/toxicidade , Iminas/toxicidade , Toxinas Marinhas/análise , Toxinas Marinhas/toxicidade , Oceanos e Mares , Filogenia , Filogeografia , Saxitoxina/análogos & derivados , Saxitoxina/isolamento & purificação , Saxitoxina/toxicidade , Intoxicação por Frutos do Mar/etiologia , Intoxicação por Frutos do Mar/patologia , Compostos de Espiro/toxicidadeRESUMO
Contamination of aquatic systems is a major environmental stress that can interfere with predator-prey interactions, altering prey or predator behavior differentially. We determined toxicity parameters of the fungicide trifloxystrobin (TFS) and examined its effects on predation rate, using a fish predator (Synbranchus marmoratus) and four anuran tadpole species as prey (Rhinella arenarum, Physalaemus santafecinus, Leptodactylus latrans, and Elachistocleis bicolor). TFS was not equally toxic to the four tadpole species, E. bicolor being the most sensitive species, followed by P. santafecinus, R. arenarum, and L. latrans. Predation rates were evaluated using different treatments that combined predator and prey exposed or not to this fungicide. TFS would alter the outcome of eel-tadpole interaction by reducing prey movements; thus, prey detection would decrease and therefore tadpole survival would increase. In addition, eels preyed selectively upon non-exposed tadpoles avoiding the exposed ones almost all throughout the period evaluated. Predation rate differed among prey species; such differences were not due to TFS exposure, but to interspecific differences in behavior. The mechanism that would explain TFS-induced reduction in predation rates remains unclear; however, what is clear is that sublethal TFS concentrations have the potential to alter prey behavior, thereby indirectly altering predator-prey interactions. In addition, we consider that predator-prey relationships are measurable responses of toxicant exposure and provide ecological insight into how contaminants modify predator-prey interactions.